Manzanita Sol has been a beverage choice at Taco Bell since January of 2014. This beverage was first introduced in 2005 as a new apple-flavored soft drink made by PepsiCo. Since then it has risen to be Pepsi's number two brand in Mexico, and has been sold in grocery stores across the United States. In January 2014, Taco Bell added this popular soft drink to their beverage lineup. Since then you have seen it at Taco Bells across the nation.
Photo by Sam's Club
We have now been told a new drink has shown up on the Taco Bell POS as well as on their soda machines. This new product is Aquafina's Berry Breeze sparkling water. Reported 3 days ago showing up on the POS system as "AQ BERRY BRZ" as well as being confirmed by multiple Taco Bell employees of this new beverage taking place of the Manzanita Sol [Source]. Today a source posted this photo to Reddit of the drink replacing the Manzanita Sol at their Taco Bell in Edgewood, PA:
Photo by garvidol on Reddit
Lastly, we have a rumor on a new Mountain Dew flavor coming to Taco Bell. All we have is the picture of a soda syrup box. Titled "Mountain Dew Goji Citrus Strawberry", this drink sounds like Mtn Dew Game Fuel Electrifying Berry. [Here] is the nutritional information PepsiCo gives on their website.
Photo by bag_of_oatmeal on Reddit
EDIT 8/31/17: New Mountain Dew flavor will be released at a gas station chain and not at any Taco Bell locations at this time.